Affiliation:
1. Department of Anatomical Sciences Renaissance School of Medicine at Stony Brook University Stony Brook New York USA
2. Center for Functional Anatomy and Evolution The Johns Hopkins University School of Medicine Baltimore Maryland USA
Abstract
AbstractObjectivesMorphological variation in African ape carpals has been used to support the idea that Pan and Gorilla evolved knuckle‐walking independently. Little work, however, has focused on the effect of body mass on carpal morphology. Here, we compare carpal allometry in Pan and Gorilla to that of other quadrupedal mammals with similar body mass differences. If allometric trends in Pan and Gorilla carpals mirror those of other mammals with similar body mass variation, then body mass differences may provide a more parsimonious explanation for African ape carpal variation than the independent evolution of knuckle‐walking.Materials and MethodsThree linear measurements were collected on the capitate, hamate, lunate, and scaphoid (or scapholunate) of 39 quadrupedal species from six mammalian families/subfamilies. Relationships between linear measurements and estimated body mass were analyzed using reduced major axis regression. Slopes were compared to 0.33 for isometry.ResultsWithin Hominidae, higher body mass taxa (Gorilla) have relatively anteroposteriorly wider, mediolaterally wider, and/or proximodistally shorter capitates, hamates, and scaphoids than low body mass taxa (Pan). These allometric relationships are mirrored in most, but not all, mammalian families/subfamilies included in the analysis.ConclusionsWithin most mammalian families/subfamilies, carpals of high body mass taxa are proximodistally shorter, anteroposteriorly wider, and mediolaterally wider than those of low body mass taxa. These distinctions may be caused by the need to accommodate relatively higher forelimb loading associated with greater body mass. Because these trends occur within multiple mammalian families/subfamilies, some carpal variation in Pan and Gorilla is consistent with body mass differences.
Subject
Paleontology,Archeology,Genetics,Anthropology,Anatomy,Epidemiology
Reference152 articles.
1. Locomotion of Animals
2. Legs and locomotion of carnivora;Alexander R. M.;Symposia of the Zoological Society of London,1993
3. Allometry of the limb bones of mammals from shrews (Sorex) to elephant (Loxodonta)